Others have also criticized the deal, believing Singleton potentially sacrificed future earnings. He took immediate financial security rather than believing in his talent and cashing in via free agency or arbitration, they say.

Singleton's deal could be worth up to $30 million over eight years because of club options, meaning he can't be a free agent until he's 30. Singleton had been on a one-year deal worth $500,000 while he was in the major leagues.